The present invention relates to a self-feed wood bit, and more particularly, to a self-feed wood bit having a feed spur having a coarse spur thread.
Self-feed wood bits are used for boring a hole through wood. The typical self-feed wood bit includes a fine thread feed spur and one or more main cutting edges extending radially outward from the center and including scoring perimeter teeth. The feed spurs are typically provided with a fine thread which acts somewhat like a screw in order to draw the self-feed wood bit into the wood so that the main cutting edge cuts away the surface of the wood. The feed spur is typically provided with a fine thread in order to limit the speed at which the main cutting edge is drawn into the wood in order to prevent binding of the wood bit which occurs if the wood bit is drawn inward too quickly. It is desirable in the art of wood bits to provide a wood bit which provides faster drilling, improved efficiency, and improved self feeding. These and other objects are obtained by providing a self-feed wood bit with a coarse thread on the feed spur and with an approximately 20 degree relief angle on the main cutting edge.
Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.